mceleoy



UNITED STATES PATENT OFFICE.

WILLIAM GARDNER AND JOHN H. MCELROY, OF PITTSBURG, PA.

FURNACE FOR GENERATING HEATING-GAS."

SPECIFICATION forming part Of Letters Patent No. 243,066, dated June 21, 1881.

Application filed February 3, 1881. (No model.) I

To all whom it may concern Be it known that we, WILLIAM GARDNER and JOHN H. MCELROY, of Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Furnaces for Generating Heating-Gas; and we do hereby declare that the following is a full, clear, and exact description of the invention, which will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, which form a part of this specification.

Figure 1 is a transverse vertical section. Fig. 2 is alongitudinal vertical section. Fig. 3 is a plan section on line :12 at, Fig. 1. Fig. 4 is a plan section on line y Fig. 2.

Our invention relates to the production of gaseous fuel for heating the retorts used in the manufacture of illuminating-gas, and the combustion of the same to produce a perfectly uniform heat.

It is a fact well understood by those engaged in the manufacture of illuminating-gas that. under existing practice it is practically impossible to maintain aperfectly uniform temperature under the retorts, even for a short time. The temperature rises and falls, and the retorts are subjected to a continual succession of expansions and contractions, which necessarily shorten their life. The charge cannot be drawn from the retorts as frequently as it is desired, and consequently a given plant cannot produce the quantity of gas which otherwise it is fitted to produce. Efforts have been made to arrive at the maximum of economy by supplying the retort-furnace with gaseous fuel produced by thedistillation or imperfect combustion of fuel and admixed with heated air; but such efl'orts have been only partially successful, owing to the fact that the air has been heated in passages or flues built in brick walls and linings, and as such walls or linings cannot be made or' maintained air-tight the supply of oxygen to the furnace cannot be reliably controlled, for the walls expand, joints open, fillings disintegrate, and even the bricks crack, and all these circumstances become active causes of leakage, and are very irregular in their occurrence. With such obstacles to uniformity it is obvious that regulating-valves would be of but little use.

Our object is to do awaywith the above difficulties and supply the retort-furnace with gaseous fuel in which the admixture of air will be completely under control,so as to'be easily regulated by valves, and the uniformity of temperature and continuity of production will be constantly preserved.

To these ends our invention consists in constructing a producer or generator consisting of a central fuel-magazine whose casing is made of metal plates joined together air-tight, and inclosing ainheating flues developed by using bricks or tiles for the magazine, having their outer periphery serrated, ashereinafte'r described, so that absolutely no air can obtain entrance to the flues except through the valveopenings, and the expansion of the magazinewalls cannot start the scams or joints of or otherwise injure the casing; and the invention consists in the combination and arrangement of parts, substantially as hereinafter fully described and claimed.

Referrin gto the accompanying drawings,our invention, more particularly, is as follows:

In front of but below each bench of retorts we construct our producer or generator. This will then stand in the room below the retortroom, and between the two coke-drop holes, which are usually found in the retort-floor in front of each bench of retorts when the benches are set in double rows.

The producer consists of a fuel-magazine or combustion-chamber, A, whose walls are generally vertical, but converge near the gratebars a, so as to form the boshes B. These walls rise nearly to the retort-floor, and are covered by a fore plate, 0, forming at that point the floor of the retort-room, in the center of which is an opening, which is hermetically closed by the cap D, luted by an additional cover,E. The magazine A is thus charged with fresh coke or other fuel from above through the fore plate, 0. The walls of the magazineAare constructed with the air-inlets F, controlled by a suitable valve. Inlet F communicates directly with an air-chamber, H, surroundingthe magazine A, and from chamber H rise vertically the airspacesz' to a mixing or gathering chamber, J, which surrounds the magazine A at or near the top. The whole producer is surrounded by an air-tight casing or shell, M, of sheet-iron or other adequate material, in which th e only openings are the doors m of the magazine-furnace and ash-pit, and the valves of inlets F. The magazine A has near its top the lateral rising flue N which conveys the gases from the magazine up into the furnace under the retorts, and two ducts, O, carry the heated air to any suitable point or points in the walls of said retortfurnace, into which they discharge and effect the perfect combustion of the gases produced in magazine A. The magazine-walls are built of bricks or blocks having their outer edges serrated, as shown in Fig. 4. The serrations are so formed as to be Weakest at their outer extremities, and may be of the regular sawtooth form, or otherwise. These blocks are built up so that the serrations of one layer or course do not exactly match those of the courses above and below it. The air-tight metallic casing M is constructed so as to nearly or quite touch these serrated blocks outside, and thus a zigzag arrangement of air-spaces is formed, in which the air becomes highly heated, and at the same time secure provision is made against damage by the expansion of the walls of the magazine, for when they do expand too much the comparatively weak points on the blocks give way and crush, thus preventing any injurious strain from coming upon the joints and seams of the metallic casing,which is thus preserved in an air-tight condition.

Thus constructed, we are enabled to readily and perfectly control the admixture of air in the retort-furnace, since no aircan by any possibility enter the retort-furnace, except what is admitted at the valves. The walls of the magazine A may expand, contract, warp, or crack indefinitely without a particle of air leaking into the air-fines. Consequently the valves become perfectly reliable, and the combustion in the retort-furnace and resultant temperature can be readily maintained absolutely constant and uniform.

By the peculiar construction of the magazine-walls with converging base the charge of fuel therein is sustained at all times,independently of the grate-bars, and hence when the bars become clogged with clinkers we can open the door m and pull out and clean the bars.

We do not claim the heating of retorts by gaseous fuel prepared exteriorly to said retorts nor do we claim, broadly, the combination of air-heatin g flues or spaces with a gas-producer; nor do we claim a producer having a metallic jacket, in the ordinary sense, but

We claim as our invention 1. A gas-producer consisting of a central fuel and combustion chamber constructed with inclosing-walls composed of blocks having a serrated periphery, in combination with an airtight metallic shield incasing the whole, substantially as described.

2. The combination ofmagaziueA,constructed of blocks or bricks having a serrated periphery, air-chamber H, air heating flues i, and an air-tight metallic casing or shield, M, having valve-controlled inlets F, communicating with said chamber H, substantially as set forth.

In testimony that we claim the foregoing as our own we have hereto affixed our signatures in presence of two witnesses.

WM. GARDNER. JOHN H. MCELROY.

Witnesses:

T. J. MCTIGHE, J. M. PATTERSON. 

